1. Field of the Invention
The present invention relates to a hose coupling device and a manufacturing method therefor, and more particularly, to a hose coupling device which is capable of easily connecting a hose by processing a pipe made of steel, copper, aluminum or resin, and to a manufacturing method therefor.
2. Description of Relevant Art
FIGS. 12A and 12B are perspective views of illustrating the procedure for assembling a ring union of a conventional hose coupling device, FIG. 12A showing the ring union in the disassembled state and FIG. 12B showing it in the finished state.
As shown in FIGS. 12A and 12B, what is called "ring union" is used in the conventional hose coupling device. The ring union comprises a steel pipe 1, a nipple 2 which is connected to one end of the pipe 1 and a ring 3 which is connected to the other end of the pipe 1 through a hole 3b formed in the side wall thereof. The nipple 2 and the ring 3 are formed by machining and firmly joined to the pipe 1 by soldering. The ring 3 is formed by boring a central hole 3a therethrough which communicates with the hole 3b in the side wall as well. The ring union is to be connected to a mating part by making use of the ring union 3 and a hose (not shown) is to be connected to the nipple 2.
Next, the connecting structure of the ring 3 and the mating part will be described. FIG. 13 is a disassembled perspective view for illustrating essential portions of the conventional hose coupling device.
As shown in FIG. 13, a bolt 4 having a hole 4a in its side is inserted in the hole 3a of the ring 3 through a washer 5, and the ring 3 is positioned above a connecting hole 8 of a mating part 7 through a washer 6. Then, by screwing the bolt 4 to the connecting hole 8 of the mating part 7, the ring 3 is firmly fixed to the mating part 7.
Further, since the ring union is allowed to rotate freely insofar as the ring 3 is merely bolted to the mating part 7 by bolt 4, a countermeasure for preventing such rotation is provided.
FIG. 14 is a perspective view illustrating the conventional hose coupling device in such a fixed state.
As shown in FIG. 14, ring 3 is prevented from rotating by positionally fixing the side wall of the ring 3 to the mating part 7 by means of a stopper plate 9.
However, in the conventional hose coupling device described above, it takes a much time to manufacture the ring union. Namely, ring 3 is formed by machining a bar material. It is also necessary to join the ring 3 and the pipe 1 together by soldering or the like. Further, in order to connect the ring union to the mating part 7, many parts, including bolt 4, are required. Moreover, the cost of the device is increased since the unit price of bolt 4 is higher than that of the conventional solid bolts. In addition, it is necessary to prevent the ring 3 from rotating by fixing the ring 3 to the mating part 7 using the stopper plate 9 or the like.